Apparatus for installing casing protectors on drill pipes



J. C. BALLAGH APPARATUS FOR INSTALLING CASING PROTECTORS 0N DRILL PIPES Filed Feb 25, 1946 illllllllrlllo Sept 19, 1950 Patented Sept. 19, 1950 APPARATUS FOR INSTALLING CASING PROTECTORS N DRILL PIPES- James-C. Ballaghg- Los Angeles, Calif., assignor, by mesneassign-ments, to Byron Jackson 00., Vernon, Calif a corporation of Delaware Application February z5, 1946,-S'erialNo. 649,856

4 Claims.

stalling casing protectors of natural or synthetic rubber on drill pipes of the type used in the rotary method of drilling oil wells.

lathe-rotary method of drilling oil-wells. casing protectors are used to prevent contact between the-drill collars andcasing. The casing protectors are sleeves of natural or syntheticrubber of suilicient thickness to protrude beyond the collars and thereby prevent contact between the'collars andthe inside of the well casing. In-installing the casing protectors on drill pipes, they must be stretched over the drill pipe and the collars on the drill pipe, an operation which has heretofore involved great difliculty. It has been suggested; in order to facilitate the installation of the protectors on drill pipes; that they be pre-stretched by the manufacturer onto a sleeve of a diameter greater than that of the drill pipe. The sleeve bearing the pre-stretched casing protector. is transported to thewell, slipped overthe drill pipe, and the casing protector forced offthe sleeve either by hydraulic pressure or forceinorder to position the protector on the drill pipe.

The present invention is concerned with apparatus for removing the casing protectorsfrom the sleeve and installing the same on the-drill D1136;

It is the general object of the presentinvention .to provide apparatusin which the necessary pressure for forcing the protector'from-the sleeve may be supplied solely from theweight of the drill pipe on which the sleeve -is-to be mounted.

The apparatus of thepresent invention .will be fully understood from the followingdescription of a preferred form or example of the invention. The description is given in connection with the accompanying drawing, in which:

Figure 1 is an elevation mainly in section of the apparatus of the present invention in the assembled position, illustrating the first'step of the op eration of the apparatus.

Figure 2 is a similar view illustrating a subsequent stepof the operation of the apparatus.

Figure 3 is a similar view of the apparatus on completion of the operation of the apparatus.

Figure 4 is a top view of the sleeve upon'iwhich the" casing protector 'is mounted.

" Figure'5 is a top view of the'cages. n

Figured is a top view of'the'cages with'the sleeve 5 therein and turned to the non-registered position.

Figure 7 is a modified form of' the apparatus showing suitable means for automatically returning the lower cage and preventing rotation between the inner and outer cases.

2 i Referring to thedrawings, I generally indicates a drill pipe of the type employed in the rotary method of drilling wells. Each drill pipe is pro+ vided at its lower end with a collar 2 of larger die ameter than the remainder of the pipe and with a tool joint 3. 4 indicates the casing protector which is normally formed of natural or synthetic rubber and as initially produced has an internal diameter smaller than that of the body of the drill pipe I so that when mounted on the drill pipe I in the position indicated in Fig. 3, the elasticity of the sleeve will provide a gripping force for holding the sleeve in position. The walls of the sleeve 4 should be of sufiicient thickness so that the external diameter of the sleeve when mounted in the position indicated in Fig. 3 is larger than thatiof the collar 2. I

In accordance with the present invention, the casing protector 4 is stretched over sleeve 5, the internal diameter of which permits the sleeve 5 to pass over the collar'2 of the drill pipe I. The sleeve 5 is provided with a flange 6 at its lower end, which flange [Les-indicated in Fig. 4, is of oval shape. There is also mounted on the sleeve 5 between the flange 6 and the casing protector 4 an annular ring I having an outside diameter somewhat larger than the minimum diameter of the oval-shaped flange'ii. I

The sleeve 5, ring. 'l and casing protector 4, assembled together as indicated in Fig. l, are transported to the well wherethe casing pro tector is to be installed upon the drill pipe and the sleeve 5 then slipped over the drill pipe in the mannerindicated in Fig. l. The drill pipe is then lowered to the stripping apparatus which consists of an outer cage 8 and an inner cage 5. The outer cage 8 is provided with cylindricalside walls It loined to a supporting flange it at its lower end, the lower end-of the cage 8 being open, agin'di'catedfat i2. 7 1 v In the operation-ofithe apparatus cf the press;

ent invention, the" outer cage member 8 is int.

tended to beremovably positioned. The upper ender, the outer cages is providedwith an oval pe g lfl (asshown in Fig. l 5) of sumeient size; tdpermit the ovalfiange E onthe sleeve 5 to pass -therethroug =h. I

the-walls hot the outer cage membere. The;

side-wallsl5 of-inner.c age member 9 are of less, length than the lengths-oi?- the wallsit; usually.

abouthalf -thelength of the walls s; but 5116' v The-innercage members! is provided with cy}- lindrical vside walls l5 having a. running-fit. with,

drill pipe, but spaced from the collar 2 sufliciently to leave proper room therebetween for the use of tongs in subsequent handling of the drill pipe. The lower end of the inner cage member 9 is provided with a tapered seat [9 to fit the threaded joint 3 of the drill pipe. The upper end of the ihner cage member 9 is provided with an oval shaped opening I? complementary to the oval opening 14 of the outer cage member 8.

The operation of the apparatus of the present invention is as follows: The sleeve 5, with the protector 4 and the ring 7 thereon, is first placed over the drill pipe but when the drill pipe I is elevated and clear of the cages 8 and 9, it is lowered into the position indicated in Fig. 1 and the oval flange 6 on the sleeve 5 is turned to pass through the oval openings in the cages 8 and 9 until the sleeve reaches the position indicated in Fig. 1 where the ring I, by contacting the upper end of the outer cage, arrests further lowering of said ring and the casing protector l mounted thereabove. The sleeve 5 is then rotated into the position shown in Fig. 6 and the weight of the drill pipe I, or a portion thereof, is then allowed to be exerted against the seat (6 f the I inner cage member, forcing the casing member downwardly. The top of the inner cage member engages the flange 6 of the sleeve 5, causing the sleeve to follow the downward movement of the cage member 9. Simultaneous movement of the ring I is arrested by the top of the other cage member with the result that, as indicated in Fig. 2, the casing protector is progressively crowded ofi the sleeve until the protector clears the sleeve and assumes the position indicated in Fig. 3. The drill pipe I, with the protector 4 now in proper position, may be elevated from the cages, the drill pipe now being in position to be set back on the rack or to be lowered into the wellhole, as the occasion may require. The sleeve 5 is then turned to register its flanges with the openings of the cages and to be removed from the cages, whereupon the apparatus is in position for the method to be repeated.

Preferably, as indicated in Fig. 7, suitable means are provided for urging or returning the inner cage 9 to the upper end of the outer cage such, for example, as the spring 18, and it is also preferable to provide means for preventing relative rotation between the inner and outer cage, such as a key I9.

While the particular form of the invention herein described is well adapted for carrying out the objects of the present invention, it is to be understood that various modifications and changes may be made, and this invention is of the scope set forth in the appended claims.

I claim:

1. Apparatus for installing acasing protecto upon a drill pipe from a transfer sleeve original- 1y mounting said protector in pre-stretched condition and adapted to pass over said drill pipe, comprising: an upstanding outer cage member supported upon a base formed at its bottom portion and having an inwardly extending flange formed at its upper portion, said flange being of such configuration as to be adapted to admit the bottom portion of said sleeve but restrain said protector against downward movement; and an inner cage member of shorter length than the outer cage member disposed within said outer cage member for vertical sliding movement therewithin, said inner cage member being formed at its upper portion with inwardly extending connection elements engageable with cooperating connection elements formed on the bottom portion of said sleeve, and being formed at its bottom portion with a surface spaced from said inwardly extending connection elements and adapted to be engaged by the lower portion of the drill pipe so that upon downward movement of said drill pipe said inner cage member and said sleeve will move downwardly in unison, whereby said sleeve will be withdrawn downwardly from said protector.

2. Apparatus for installing casing protectors on drill pipe comprising: a sleeve adapted to pass over the drill pipe and to carry a protector in a pre-stretched condition; an upstanding outer cage member supported upon a base formed at its bottom portion and having an inwardly extending flange formed at its upper portion, said flange being of such configuration as to be adapted to admit the bottom portion of said sleeve but restrain said protector against downward movement; and an inner cage member of shorter length than the outer cage member disposed within said outer cage member for vertical sliding movement therewithin, said inner cage member being formed at its upper portion with inwardly extending connection elements engageable with cooperating connection elements formed on the bottom portion of said sleeve, and being formed at its bottom portion with a surface spaced from said'inwardly extending connection elements and adapted to be engaged by the lower portion of the drill pipe, so that upon downward movement of said drill pipe said inner cage member and said sleeve will move downwardly in unison, whereby said sleeve will be withdrawn downwardly from said protector.

3. Apparatus as set forth in claim 2 wherein the transfer sleeve is formed with an outwardly extending oval flange at its bottom portion and the inner cage member is formed at its upper portion with an inwardly extending flange defining an oval-shaped aperture, said aperture being slightly larger than the oval flange of said sleeve whereby said oval flange will pass through said aperture in one relative position thereof and will be restrained against passage therethrough in other positions.

4. Apparatus as set forth in claim 1 wherein a spring is provided within said outer cage member having its one extremity abutting the base thereof, and having its other extremity abutting said inner cage member whereby to normally urge said inner cage member'upwardly.

1 JAMES C. BALLAGH.

REFERENCES CITED The following references are of record in the file ofthis patent:-

UNITED STATES PATENTS Number Name Date 1,320,378 Burdette Nov. 4, 1919 1,965,876 Bettis July 10, 1935 2,252,692 Barnes Aug. 19, 1941 2,270,671 Hall Jan. 20, 1942 2,320,553 Barnes -.June 1, 1943 2,328,771 Barnes et a1 Sept. 7, 1943 2,334,557 Howard Nov. 16, 1943 2,429,341 Ballagh Oct. 21, 1947 2,440,009 G ahame.-. Apr. 20, 1948 

